In a CV you don't have to put what sort of job you are looking for. Just state all the things you need to (and all the areas you need to cover: education, employment history etc.). If you want to explain why you want to work there put it in a covering note. A covering note would probably be the best place to say what job you are looking for, why you would like it, to thank them for taking the time to read it etc.
How bad are the grades? Can you just put how many GCSEs you passed?
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Greater than a poet's fame
A little grave that has no name.